Do you mean to automatically detect whether the tweet of a certain user contains a certain hashtag, and then automatically retweet and like it?
In fact, this is impossible to do. But you can use the Twitter retweet and like service to help you monitor the status of tweets posted by an user in real time, and then filter according to the hashtag, and then automatically like and retweet.
In case you are searching for this service, you can try this twitter auto like and retweet service
Using this service, not only can you automatically retweet and like posts, you can also automatically follow, unfollow and send a message to someone...ect. The specific operation screenshots are as follows.
Web page: https://www.whitehatbox.com/
Skype id: live:alvaeyer
If you encountered any problem, please feel free to contact us at Skype or email us at rrebeca535@gmail.com